The present invention relates generally to diagnostic instruments and, more particularly, to a lancet-release mechanism for a lancing device.
The quantitative determination of analytes in body fluids is of great importance in the diagnoses and maintenance of certain physiological abnormalities. For example, lactate, cholesterol and bilirubin should be monitored in certain individuals. In particular, determining glucose in body fluids is important to diabetic individuals who must frequently check their blood glucose levels to regulate the glucose intake in their diets.
One method of obtaining a body fluid sample, such as a whole blood sample, is to use a lancing device. The whole blood sample may then be used to determine the glucose concentration of an individual. Existing lancing devices use a lancet to pierce the tissue of the skin, allowing a blood sample to form on the skin's surface. Typically, lancing devices hold the lancet within them when the lancet is not in use, so as to shield the user from injury as well as to assist in preventing or inhibiting contamination.
Existing lancing devices require are potentially dangerous when—or are ineffective in—releasing the lancet. Typical two-handed operation requires that one hand hold the lancing device while the other hand removes the lancet. This is inconvenient to many users as the lancet is small, and may cause safety problems as the lancet could pierce the user's skin inadvertently. This can cause user pain and may also transmit diseases. Some lancet-release designs have complicated release mechanisms internally, such that if a user drops the lancing device, the release mechanism may jam and no longer eject the lancet from the lancing device.
It would be desirable to have a lancing device and a method for using a lancing device that address these issues.
According to one embodiment of the present invention, a lancing device is disclosed. The lancing device comprises a main housing, a movable housing, and a pushbutton. The main housing encloses a portion of a lancing mechanism including a lancet holder attached to a shaft. The lancet holder is adapted to receive a lancet and has a slot formed therein. The lancing mechanism is adapted to move between a rest position, a cocked position, and a puncture position. The movable housing is adjacent the main housing and is adapted to move from a rest position to a cocking position and a lancet-release position. The pushbutton is adapted to allow the lancing mechanism to move from the cocked position to the puncture position upon depression of the pushbutton in the general direction of the main housing. The pushbutton includes a lancet-release tab formed thereon. The lancet-release tab is adapted to extend into the slot formed in the lancet holder and engage the lancet. The lancet is released from the lancet holder in response to the continued depression of the pushbutton and the movable housing being moved from the rest position to the lancet-release position.
According to another embodiment of the present invention, a method of releasing a lancet from a lancing device is disclosed. The method comprises the act of providing a lancing device including (i) a main housing enclosing a lancet holder being adapted to receive the lancet, the lancet holder having a slot formed therein, (ii) a movable housing adjacent the main housing, the movable housing being adapted to move from a rest position to a cocking position and a lancet-release position, and (iii) a pushbutton having a lancet-release tab formed thereon, the lancet-release tab being adapted to extend into the slot formed in the lancet holder and engage the lancet. The method further comprises the act depressing the pushbutton in the general direction of the main housing resulting in the lancet-release tab entering the slot formed in the lancet holder. The method further comprises the act of moving the movable housing from the rest position to the lancet-release position, while the pushbutton remains depressed. The movement of the movable housing causes the lancet-release tab to engage the lancet and cause the lancet to release from the lancet holder.
The above summary of the present invention is not intended to represent each embodiment, or every aspect, of the present invention. Additional features and benefits of the present invention are apparent from the detailed description and figures set forth below.
a-b are perspective views of a lancing mechanism, contained within the lancing device of
a is a cross-sectional side view of the lancing device—taken generally along line 10-10 of FIG. 1—in a cocked position, according to one embodiment of the present invention.
b is a cross-sectional side view of the lancing device of
c is a cross-sectional side view of the lancing device of
The present invention is directed to a lancing device that is adapted to receive and release a lancet for use in drawing a body fluid from a test subject. The body fluid generally contains at least one analyte that may then be examined to determine its concentration in the body fluid sample.
Lancing devices and lancets may be used to produce a blood or body fluid sample from a test subject. This sample may then be analyzed with a meter and test strip, or similar devices, to determine the concentration of the analyte to be examined. Examples of the types of analytes that may be collected with a lancing device include glucose, lipid profiles (e.g., cholesterol, triglycerides, LDL and HDL), microalbumin, hemoglobin A1C, fructose, lactate, or bilirubin.
Turning now to the drawings and initially to
When used, the movable housing 14 is pulled away from the main housing 12 to move an internal lancing mechanism 24 (
Referring also to
The movable housing 14 has a pair of elongated columns 48a,b integrally formed therewith. Each of the columns 48a,b extends into the main housing 12 through an aperture (not shown) formed in the first main-housing portion 12a. A secondary spring 46 is disposed around the shaft 38 within the movable housing 14. A first end of the secondary spring 46 is disposed against an internal surface of the movable housing 14 and a second end of the secondary spring 46 is disposed against the retainer 40 of the shaft 38. The secondary spring 46 is centrally located within the movable housing 14 along the longitudinal axis of the lancing device 10.
Referring now to
Once the angled stop members 50a,b have moved past the ends 53a,b of the catch arms 52a,b, a spring mechanism 82 (illustrated in
The lancet holder 36 is guided between its resting and cocked positions by a guide rib 56 (
To perform a puncture on a test subject's skin, the endcap 18 is attached to the lancing device 10. The lancet holder 36 may be in the cocked position at the time the endcap 18 is attached or may be cocked once the endcap 18 has been removably attached to the endcap support 16. The endcap 18 is then placed firmly against the skin where the puncture is to be made, and the pushbutton 22 is depressed. Depressing the pushbutton 22 causes the catch arms 52a,b (FIG. 8)—integrally formed with the bottom of the pushbutton 22—to move toward the first main-housing portion 12a away from the lancet holder 36. Thus, the lancet holder 36 is no longer prevented from moving in the direction of Arrow B by the contact of the ends 53a,b of the catch arms 52a,b with the angled stop members 50a,b of the lancet holder 36. The spring mechanism 82 of
Upon release of the lancet holder 36 as described above, the drive spring 42 will force the lancet holder 36 in the direction of Arrow B until the sharp point of the lance 34 (
However, the lancet holder 36 typically moves in the direction of Arrow A further than required to return to its rest position. Thus, slightly recompressing the drive spring 42, which causes the lancet holder 36 to again travel in the direction of Arrow B. As the lancet holder 36 begins to move back in the direction of Arrow B (due to the slight recompression of the drive spring 42), the secondary spring 46 is recompressed. The force required to recompress the secondary spring 46 effectively dampens the movement of the lancet holder 36. Such damping assists in inhibiting or preventing the drive spring 42—and its natural tendency to oscillate (due to its being elastically deformable)—from causing a second, unintended skin puncture.
Turning now to
Turning now to
The lancet holder 36 includes the guide rib 56 that is adapted to be inserted into the groove 58 (
As best illustrated in
Turning now to
Referring now to
As the lancet holder 36 moves in the direction of Arrow A, the lancet-release tab 76 engages the lancet 30 and inhibits the lancet 30 from moving in the direction of Arrow A. As the lancet holder 36 continues to move in the direction of Arrow A, the lancet 30 is removed from the lancet holder 36 without the user having to directly contact the lancet 30 with their hand. Once the lancet 30 has been released, the user releases the movable housing 14 and the secondary spring 46 causes the movable housing 14 to move in the direction of Arrow B until the movable housing 14 is once again adjacent the main housing 12.
As should be apparent from the above-described lancet-release mechanism, the potential for unintended punctures to the user is greatly diminished. In addition, the lancet-release mechanism is designed to be easily integrated into existing lancing devices 10 and, because of its unique design, is well-suited to stand the everyday use of a user of the lancing device 10 (e.g., carrying in a purse or pocket, dropping, inadvertent bumping, etc.).
In the above-described lancing device 10, the secondary spring 46 is used to both move the movable housing 14 from the cocking position to the cocked position as well as to return the lancet holder 36 from its puncture position to its rest position. In addition, the secondary spring 46 is adapted to move the movable housing 14 from the lancet-release position to the rest position.
The use of two opposing springs allows for the puncture strength to be adjusted by adjusting the spring ratio between the drive spring 42 and the secondary spring 46, reducing the need to compute the frictional interaction and mass of the various components of the device. Typically, the spring constant of the drive spring 42 is greater than the spring constant of the secondary spring 46, which causes the secondary spring 46 to initially be compressed by the force provided by the drive spring 42.
The structure of the above-described lancing device 10 also allows for both the drive spring 42 and the secondary spring 46 to remain free floating on the shaft 38. Thus, the need for attaching one or both ends of each spring is eliminated, reducing the cost and time required to manufacture the lancing device 10.
A lancing device comprising:
a main housing enclosing a portion of a lancing mechanism, the lancing mechanism including a lancet holder attached to a shaft, the lancet holder being adapted to receive a lancet and having a slot formed therein, the lancing mechanism being adapted to move between a rest position, a cocked position, and a puncture position;
a movable housing adjacent the main housing, the movable housing being adapted to move from a rest position to a cocking position and a lancet-release position; and
a pushbutton adapted to allow the lancing mechanism to move from the cocked position to the puncture position upon depression of the pushbutton in the general direction of the main housing, the pushbutton including a lancet-release tab formed thereon, the lancet-release tab being adapted to extend into the slot formed in the lancet holder and engage the lancet,
wherein the lancet is released from the lancet holder in response to the continued depression of the pushbutton and the movable housing being moved from the rest position to the lancet-release position.
The lancing device of Alternative Embodiment A, wherein the pushbutton of the lancet-release mechanism includes a depression that assists a user in engaging the pushbutton.
The lancing device of Alternative Embodiment A, wherein the pushbutton of the lancet-release mechanism includes tactile features that assist a user in engaging the pushbutton.
The lancing device of Alternative Embodiment A, wherein the lancet-release tab does not engage the lancet until the movable housing is moved from the rest position to the lancet-release position.
The lancing device of Alternative Embodiment A, wherein the cocking position and the lancet-release position of the movable housing are substantially identical.
A method of releasing a lancet from a lancing device, the method comprising the acts of:
providing a lancing device including,
depressing the pushbutton in the general direction of the main housing resulting in the lancet-release tab entering the slot formed in the lancet holder; and
moving the movable housing from the rest position to the lancet-release position, while the pushbutton remains depressed, the moving of the movable housing causing the lancet-release tab to engage the lancet and cause the lancet to release from the lancet holder.
The method of Alternative Process F, further comprising the act of removing the lancet from the lancet holder without a user touching the lancet.
The method of Alternative Process F, wherein the pushbutton is also adapted to fire the lancing device.
The method of Alternative Process H, wherein the pushbutton is utilized to release the lancet from the lancet holder.
The method of Alternative Process F, wherein the cocking position and the lancet-release position of the movable housing are substantially identical.
While the invention is susceptible to various modifications and alternative forms, specific embodiments and methods thereof have been shown by way of example in the drawings and are described in detail herein. It should be understood, however, that it is not intended to limit the invention to the particular forms or methods disclosed, but, to the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US07/06225 | 3/12/2007 | WO | 00 | 2/2/2010 |